Boolos, George <br/><br/>
The logic of provability 
George Boolos 
 - Cambridge  Cambridge University Press  1993 
 - xxxvi, 275 p. ; 24 cm 
<br/><br/> Includes bibliographical references (p. [262]-269) and index 
<br/><br/><label>ISBN: </label>9780521483254 
<br/><br/><label>ISSN: </label>92043610 
<br/><br/><label>Subjects--Topical Terms: </label><br/>Modality (Logic)<br/>Proof theory
<br/><br/><label>Dewey Class. No.: </label>160 BOO